The present invention relates to an improved nozzle for use in a cooling tower and in addition to a cooling tower equipped with this improved nozzle.
The construction and operation of cooling towers are well known in the art. In this regard, see Perry's Chemical Engineers Handbook, 4th Edition, McGraw-Hill Book Co., Inc., copyright 1963, pp. 15-14 to 15-23, the disclosure of which is incorporated herein by reference.
As is well known, cooling towers are used for cooling a liquid, usually water, which is used in a manufacturing plant or other facility for cooling the equipment being operated therein. Normally, a cooling tower includes a chamber for effecting contact between liquid falling through the chamber and air passing through the chamber. During intimate contact of the air and liquid, a portion of the liquid evaporates, thereby cooling the remaining liquid so that a cooler liquid product is obtained. In order to effect intimate contact between the liquid to be cooled and the air in the cooling tower, the liquid is normally formed into droplets prior to contacting air, this being done by spraying the liquid into an upper portion of the cooling tower chamber by means of one or more nozzles of suitable design.
As appreciated by those skilled in the art, the operating efficiency of a cooling tower is dependent, among other factors, upon the total surface area available for gas/liquid contact, i.e., the total surface area of all the liquid particles being contacted with air in the cooling tower chamber. Therefore, it is desirable to spray the liquid to be cooled in the cooling tower chamber in the form of fine droplets, since fine droplets present a very large total surface area of gas/liquid interface. On the other hand, if the liquid droplets become too small in size, as for example when the liquid forms a mist, they exhibit a tendency to be carried along with the air passing through the cooling tower chamber. If this should occur, a significant portion of the liquid introduced into the cooling tower will be lost from the system without providing a cooling effect. Consequently, it is also desirable that the particle size of the liquid particles is not too small.
Although different types of nozzles for use in cooling towers are available in the market at this time, most of these nozzles are disadvantageous for one reason or another. For example, most conventional nozzles are constructed in such a way that liquid passing therethrough forms an umbrella-like sheet as it falls away from the nozzle. The liquid in this umbrella-like sheet then breaks up into individual droplets as it travels farther away from the nozzle. Because the liquid emanating from the nozzle first forms an umbrella-like sheet before breaking up into particles, the total surface area of the gas/liquid interface remains small until the liquid travels a significant distance away from the nozzle. Also, because formation of droplets from the liquid in the umbrella-like sheet does not significantly alter the trajectory of the liquid, the liquid droplets tend to remain in an umbrella-like configuration, thereby causing the distribution of liquid droplets below the nozzle to be non-uniform. For these reasons, the heat-exchange efficiency of a cooling tower equipped with such a nozzle is reduced, and consequently the size of a cooling tower equipped with such a nozzle must be increased in order to realize a given cooling capacity.
Another disadvantage associated with many conventional nozzles for use in cooling towers is that they are subject to plugging and clogging. In many instances, the cooling liquid to be processed by a cooling tower contains corrosives and debris which will completely clog the tower nozzles during normal operation. Therefore, it is necessary in such installations to periodically shut down the cooling tower and clean the nozzles therein to prevent the nozzles from becoming completely clogged. This, of course, is disadvantageous not only because the operation of the cooling tower must be interrupted but also because cleaning of the nozzles can often be difficult and dangerous for maintenance personnel.
Accordingly, it is an object of the present invention to provide an improved nozzle for use in cooling towers which is capable of distributing the cooling liquid in the cooling tower chamber in such a way that the cooling capacity of the cooling tower is increased.
In addition, it is another object of the present invention to provide an improved nozzle for use in a cooling tower which will experience little or no clogging or plugging even when the liquid to be processed contains corrosives and debris.
A still further object of the present invention is to provide an improved nozzle for use in a cooling tower which is of simple construction and hence easy to manufacture.
Still another object of the present invention is to provide an improved cooling tower equipped with the cooling tower nozzle of the present invention.